Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3b0aa150705ad99…

MALICIOUS

PDF

75.6 KB Created: 2021-09-08 20:52:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a843436bca3eb06779d3633ba5010385 SHA-1: 2ca320cbad96ee7b730f43464d0964d8dccaa9eb SHA-256: c3b0aa150705ad99aed89f43336972ef6121dde74ae6ab024ed15fb4d3100042
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external links, with a significant number pointing to disposable hosting, indicating a link farm designed to obscure the ultimate destination. One high-severity heuristic specifically flagged a link to an algorithmically-generated URL, suggesting a malicious intent to distribute further payloads or conduct phishing. While no scripts were directly extracted, the PDF structure and link farm heuristic strongly suggest it's a delivery mechanism for malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://hertzlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/23669309121.pdf In PDF document text
    • http://kursverwaltung.fit-n-essen.ch/ckfinder/userfiles/files/4687830711.pdfIn PDF document text
    • http://3suntech.com/UploadFile/file/20210901062332615.pdfIn PDF document text
    • http://topstec.com/d/files/jijodupadaluvubikap.pdfIn PDF document text
    • https://cantellodetersiviprofessionali.it/uploads/file/tedujebaneludugano.pdfIn PDF document text
    • http://arcos-eff.it/userfiles/files/minuvoroxitejerowusibefed.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130329ea96c3---fosukadizez.pdfIn PDF document text
    • http://mdbim.pl/ubezpiecz/obrazy/file/mabilaxev.pdfIn PDF document text
    • http://vititanon.com/user_img/files/99237713462.pdfIn PDF document text
    • http://budropol.de/Upload/file/34536878352.pdfIn PDF document text
    • https://bem-sa.com/img/file/nexugojutepis.pdfIn PDF document text
    • http://vigova.com/Images_upload/files/zijus.pdfIn PDF document text
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/b0aef5e9479eec3a77b7897bd866d384/xifozobibev.pdfIn PDF document text
    • https://freshchannels.com/home/sites/freshchannels/public_html/ckfinder/userfiles/files/mugapupu.pdfIn PDF document text
    • https://btsis.com/upload/ckfinder/files/zikon.pdfIn PDF document text
    • http://jonme.net/ckupload/files/gidedidofewelusi.pdfIn PDF document text
    • http://salwex.hu/file/xidasoli.pdfIn PDF document text
    • http://kool-house.com/upload/editor/file/3442099509.pdfIn PDF document text
    • http://mnwebdesign.dk/userfiles/file/76333911655.pdfIn PDF document text
    • http://chiangmaicharmingtravel.com/ckfinder/userfiles/files/jokojulutusazawewunasi.pdfIn PDF document text
    • http://hzxf.com/images/upload/File/bejamedexovutu.pdfIn PDF document text
    • http://canxetaidientu.com/images/file/68329460538.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=bill+nye+motion+worksheet+freePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c519.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC519 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD30 10660 bytes
SHA-256: 5db4b9dc8fb9c14dfc4fad2239926e3a165234228b52d3a33ec578611f9a4b69
font_02_sfnt_off0000f577.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF577 16588 bytes
SHA-256: 86b086109d799f45ea1cdaba6be5f76befd25018c8e01448631fa93b92f9cc2b